STUDY ON THE NOVEL TRANSFORMER PROTECTION PRINCIPLE BASED ON THE TRANSFORMER MODEL

For the problem of discrimination between inrush current and internal fault current, this paper presents the basic principle of the novel transformer protection method based on the transformer model. Its operation equations of two-winding and three-winding transformer are derived from this principle. And the transformer protection method is presented. The method can be unacted on the inrush current and does not need the internal parameters got difficultly. The results of testing confirmed that the method is able to clear the internal fault reliably and quickly.